"I made a mistake."
A mistake is forgetting your hat.
A mistake is tripping over a step you had forgotten.
A mistake is reading "1 tspn salt" in a cake recipe, and putting in a Tablespoon.
A mistake is missing your exit.
A mistake is setting your alarm, neglecting to change it from "PM" to "AM."
A mistake is not a consistent and imaginative course of action that involves multiple crimes that were committed over 6 years.